Jack Dorsey, chief executive officer and co-founder, said in a tweet yesterday that he lost 200,000 followers, bringing his total down to four million, after Twitter made good on its pledge to remove suspicious accounts.

On Wednesday, Vijaya Gadde, Twitter’s head of legal, policy, trust and safety, said the company would begin removing “locked accounts from follower counts across profiles globally. As a result, the number of followers displayed on many profiles may go down.” Locked accounts are those identified to have involved sudden suspicious changes in activity.

In his tweet Thursday, Dorsey said, “Action on this starts today.”

The company recently said it’s identifying almost 10 million dubious accounts a week and is putting all accounts through a security check. The Washington Post reported last week that Twitter has suspended more than one million accounts a day in recent months, and the rate has more than doubled since October, when the company, under congressional pressure, revealed how Russians used fake accounts to manipulate the US presidential election.

Other high-profile figures also took a hit to their numbers of followers. President Donald Trump, one of the most prolific and high-profile tweeters, lost about 100,000 of his approximately 53.4 million Twitter followers, according to the Washington Post, and former President Barack Obama lost about 400,000 from his 104 million followers. Katy Perry, currently the most-followed person on Twitter, had more than 109 million followers Wednesday — a number that plunged to about 108 million yesterday afternoon. — Bloomberg